Consolidating HP Serviceguard for Linux and Oracle RAC 10g Clusters, June 2005

In an Oracle 10g R1 RAC on Linux environment, only configurations leveraging
Serviceguard for Linux as the failover cluster solution for applications other than the Oracle
database will be supported by HP.
Audience
This document is for users of Serviceguard on Linux who are interested in providing high
availability encapsulation to applications which would run on the same servers as an Oracle
10g R1 RAC cluster. It documents the guidelines to implement a stable dual-cluster, with
Serviceguard for Linux and Oracle 10g R1 RAC database.
It is assumed that the reader has a general understanding of Serviceguard for Linux and
Oracle 10g R1 RAC cluster features. Please see
www.hp.com/go/sglx and
www.hp.com/solutions/highavailability/oracle for detailed information on each solution.
Consolidating HP Serviceguard for Linux and Oracle RAC
10g Clusters
Background
On Linux, Oracle mandates that CRS be used to derive membership for the RAC cluster and
disallows the use of any other clustering software for this purpose. This is different than HP-
UX. For Oracle RAC on HP-UX, a special version of Serviceguard, Serviceguard Extension
for RAC (SGeRAC), provides membership control for both clusters.
However Oracle does not provide any high availability features with RAC for other
applications that customers may run on the same nodes of the cluster. Serviceguard for
Linux, running on the same cluster hardware as Oracle RAC, can provide the high
availability encapsulation for such applications. The two clusters run independently of one
another, sharing no data or control. To maintain that independence, any Oracle RAC data
on shared storage should not be part of any Serviceguard package.
Independently running two cluster software products, on the same set of nodes and
hardware resources poses a unique set of challenges, most important of these being the
ability to reduce conflicts between the two.
Dual Cluster Co-existence
The function of a high availability cluster is to keep applications available. In order to
provide that capability the cluster software needs to be able to monitor the state of
applications and also the state of the various nodes in a cluster. In the case of Serviceguard
for Linux and Oracle RAC co-existence, there is no “overlap” in monitoring applications,
since Oracle monitors only the RAC application and Serviceguard monitors any other
application. Both Serviceguard for Linux and RAC are monitoring the same nodes using
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